▎ 摘　　要

NOVELTY - Preparing upconversion fluorescent recognition probe comprises (i) preparing UCNPs-OA using hydrated rare earth chloride, 1-octadecene, oleic acid, sodium hydroxide and ammonium fluoride, and modifying UCNPs-OA by ligand exchange method to obtain water-soluble upconversion fluorescent nanomaterial UCNPsCOOH, (ii) choosing specific genes according to the species of pathogenic bacteria, using molecular biology and DNA nanotechnology to design nanoprobe ssDNA with specific and accurate identification of species nucleic acid base sequence, and using chemical synthesis method to prepare and modify with amino groups to obtain amino functionalized DNA nanoprobes, and (iii) connecting UCNPs-COOH obtained in step (i) with the amino functionalized DNA nanoprobes obtained in step (ii) through EDC/NHS amide condensation reaction to obtain the up-conversion fluorescent recognition probe. USE - The up-conversion fluorescent recognition probe is useful in detection of pathogenic bacteria in food (claimed). ADVANTAGE - The probe combines the stable luminescence properties of UCNPs, specific and precise identification function of DNA nanoprobes and the excellent fluorescence quenching performance of GOQDs, thus improving the sensitivity and specificity of detection. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) up-conversion fluorescent recognition probe prepared by above method; and (2) molecular detection of pathogenic bacteria based on fluorescent nanomaterials and DNA nanotechnology, comprising using the up-conversion fluorescent recognition probe.